2HSS86H Driver... AC or DC PSU?

[JW1977]

Hi!

I’m currently in "PSU build mode".
My drivers (JMC 2HSS86H) can be run with 24-70V DC or 30-100V AC.

Whats the pros and cons by running them on AC?
Would the PSU look the same, with capacitors but without the rectifier?

I´ve got 4 drivers and 4 motors. 3 Nm Hybrid, 1,8 mH, slaved Y-axis.
Working plan resulted in components that would give the drivers 48V and a 600-700 W PSU.

Would it be a mistake running 2 switched PSU´s of 350W each instead of a DIY Thoroidal PSU?
It’s cheaper but how about ripple and back current?

Thanks
/J

[Clive S]

Hi!

I’m currently in "PSU build mode".
My drivers (JMC 2HSS86H) can be run with 24-70V DC or 30-100V AC.

Whats the pros and cons by running them on AC?
Would the PSU look the same, with capacitors but without the rectifier?

I´ve got 4 drivers and 4 motors. 3 Nm Hybrid, 1,8 mH, slaved Y-axis.
Working plan resulted in components that would give the drivers 48V and a 600-700 W PSU.

Would it be a mistake running 2 switched PSU´s of 350W each instead of a DIY Thoroidal PSU?
It’s cheaper but how about ripple and back current?

Thanks
/J

Re the AC input 3-100 you would not use caps just a transformer with a secondary of about 7--80 v

If you want to go down the DC route then a toroidal power supply is a better choice using a 22-0-22 secondary would give you about 62V DC when rectified with caps.

[JW1977]

But if i choose to go AC there will not be any capacitors handling the back EMF from the motors right?

[Clive S]

But if i choose to go AC there will not be any capacitors handling the back EMF from the motors right?

The caps are in the drives. You can't put caps on the transformer without the rectifier before them.

edit
My drivers (JMC 2HSS86H) can be run with 24-70V DC or 30-100V AC.
Are you sure you have this the correct way round

[JW1977]

This is from the manual but im still leaning towards going DC.
After all, its quite fun building the PSU... :smile:
24825

[Clive S]

This is from the manual but im still leaning towards going DC.
After all, its quite fun building the PSU... :smile:
24825

So yes you had it the wrong way round. I would up the toroidal transformer to 25- 0 - 25 which would give you about 70v dc when rectified . good vid here. https://www.youtube.com/watch?v=4OoQQg76ar4&list=PL1FIADAKba_tiLqXbUkzD30sZjtp_VyqY

[JW1977]

Ok, thanks but i don’t get where I’m wrong, could you please explain?

As i see it i have the choice to run them with AC and a PSU consisting of only a thoridal transformer.

The other alternative would be DC and a PSU with transformer, rectifer and caps.
The motors have 1,8 mH inductance so I figured a 48V PSU would be sufficient to get speed and reduce heat and back EMF.

Heres Another schematic where it says AC or DC as Power supply!?

24826

[Clive S]

Ok, thanks but i don’t get where I’m wrong, could you please explain?

As i see it i have the choice to run them with AC and a PSU consisting of only a thoridal transformer.

The other alternative would be DC and a PSU with transformer, rectifer and caps.
The motors have 1,8 mH inductance so I figured a 48V PSU would be sufficient to get speed and reduce heat and back EMF.

Heres Another schematic where it says AC or DC as Power supply!?

24826

Ok when I said you had it wrong I was referring to "My drivers (JMC 2HSS86H) can be run with 24-70V DC or 30-100V AC" you have the DC and AC transposed .

You indicated that you would be leaning towards DC.

You can have either a transformer with caps and a rectifier OR just a transformer.

Forget about the back EMF the caps take care of that ( there are caps in the driver as well) The heat is what you set the current to on the drive.

If you want speed for wood routing then a higher voltage PS is beneficial. I would go with 70V DC but your choice.

[JW1977]

Ok, got it! :smile:
I´m gonna take your advice regarding the PSU and build a DC one with higher Voltage.
Thanks!

[Clive S]

Ok, got it! :smile:
I´m gonna take your advice regarding the PSU and build a DC one with higher Voltage.
Thanks!

Ok don't worry about asking questions its cheaper than getting it wrong. Check out Joe's vid its a good guide.

This is a good place for a one stop shop https://www.rapidonline.com

[JW1977]

Ok, thanks! :smile:

[JW1977]

Hi!

I’m about to get the remaining parts that I need for the PSU and I would need some input.
Here is what I got so far.

Toroidal transformer, 2x36V, 800 VA. I intend to wire the secondary in parallel to get about 48V rectified.
A cap rated 80V, 27000 uF.

Looking at a rectifier rated at 600V 35A. I learned that the rectifier values should exceed the actual values.
My steppers are rated at 5 amps max and there’s 4 of them. Is it a problem choosing a rectifier that exceed the actual Volts to much?

Do I need a bleed resistor over the cap? If so, any recommendations of the proper value of the resistor?

Any recommendations regarding fuses? Type, value and so on?
I don’t know what they are called in English but I have seen like a flip fuse mounted on a din rail beside the PSU.

Volt readouts?

Would appreciate some input and input in general here, thanks! :smile: